Tunable silencer for air handling unit

Patent metadata

Field	Value
Publication number	US-12283262-B2
Application number	US-202217848166-A
Country	US
Kind code	B2
Filing date	Jun 23, 2022
Priority date	Jun 24, 2021
Publication date	Apr 22, 2025
Grant date	Apr 22, 2025

Abstract

A silencer module for an air handling unit includes a first baffle and a second baffle spaced apart from the first baffle to form an air channel between the first baffle and the second baffle. The air channel is configured to receive a fluid flow and direct the fluid flow through the silencer module. The silencer module also includes a reactive acoustic feature formed in the first baffle. The reactive acoustic feature includes an attenuation profile configured to reduce propagation of tonal acoustic waves through the air channel.

First claim

The invention claimed is:

1. A silencer module for an air handling unit, comprising:
a first baffle comprising a first plurality of panels defining a first interior volume of the first baffle and a first outer perimeter of the first baffle;
a second baffle spaced apart from the first baffle to form an air channel between the first baffle and the second baffle, wherein the air channel is configured to receive a fluid flow and direct the fluid flow through the silencer module; and
a reactive acoustic feature formed in the first baffle within the first outer perimeter of the first baffle, wherein the reactive acoustic feature comprises an attenuation profile configured to reduce propagation of tonal acoustic waves through the air channel, and the reactive acoustic feature is separated from the first interior volume via a first plurality of walls of the first baffle.

2. The silencer module of claim 1 , wherein the first plurality of panels comprises a first panel that bounds a portion of the first interior volume of the first baffle, the second baffle comprises a second plurality of panels, the second plurality of panels comprises a second panel that bounds an additional portion of a second interior volume of the second baffle, and the air channel is formed between the first panel and the second panel.

3. The silencer module of claim 2 , wherein the reactive acoustic feature comprises:
a throat extending through the first panel; and
a resonator chamber fluidly coupled to the throat, wherein a first dimension of the throat along an axis of the air channel is less than a second dimension of the resonator chamber along the axis of the air channel.

4. The silencer module of claim 3 , wherein the throat comprises:
a first subset of the first plurality of walls extending from the first panel; and
a second subset of the first plurality of walls extending from resonator walls of the first plurality of walls defining the resonator chamber, wherein the second subset of the first plurality of walls is moveable relative to the first subset of the first plurality of walls to adjust a length of the throat.

5. The silencer module of claim 1 , wherein the first baffle comprises:
perforations configured to fluidly couple the air channel with the first interior volume of the first baffle; and
sound absorbing material disposed within the first interior volume and configured to absorb broad band acoustic waves to reduce propagation of the broad band acoustic waves through the air channel.

6. The silencer module of claim 5 , wherein the sound absorbing material comprises fiberglass, mineral wool, steel wool, foam, natural cotton, micro-perforated metal, or a combination thereof.

7. The silencer module of claim 1 , comprising an additional reactive acoustic feature formed in the second baffle, wherein the additional reactive acoustic feature comprises an additional attenuation profile configured to reduce propagation of the tonal acoustic waves through the air channel.

8. The silencer module of claim 7 , wherein the reactive acoustic feature and the additional reactive acoustic feature are positioned in a parallel configuration with respect to an axis of the air channel.

9. The silencer module of claim 7 , wherein the reactive acoustic feature and the additional reactive acoustic feature are positioned in a series configuration with respect to an axis of the air channel.

10. The silencer module of claim 7 , wherein the reactive acoustic feature includes a resonator chamber having a first volume, and the additional reactive acoustic feature includes an additional resonator chamber having a second volume greater than the first volume.

11. The silencer module of claim 1 , wherein the reactive acoustic feature comprises a quarter wave tube.

12. A baffle for a silencer module of an air handling unit, comprising:
a shell comprising a plurality of panels defining an interior volume of the baffle and defining an outer perimeter of the baffle, wherein the plurality of panels comprises a panel having perforations formed therein;
a reactive acoustic feature formed within the outer perimeter of the baffle, wherein the reactive acoustic feature comprises a throat in fluid communication with an air passage external to the shell, the reactive acoustic feature comprises an attenuation profile configured to attenuate tonal acoustic waves, and the reactive acoustic feature is separated from the interior volume by a plurality of walls of the baffle; and
a sound absorbing material disposed within the interior volume, wherein the sound absorbing material is fluidly coupled to the air passage via the perforations, and wherein the sound absorbing material is configured to attenuate broad band acoustic waves.

13. The baffle of claim 12 , wherein the reactive acoustic feature includes a resonator chamber fluidly coupled to the throat, a first width of the throat is less than a second width of the resonator chamber, the throat is defined by throat walls of the plurality of walls, and the resonator chamber is defined by resonator walls of the plurality of walls.

14. The baffle of claim 12 , wherein the reactive acoustic feature comprises a quarter wave tube.

15. The baffle of claim 12 , wherein the sound absorbing material comprises fiberglass, mineral wool, steel wool, foam, natural cotton, micro-perforated metal, or a combination thereof.

16. The baffle of claim 12 , comprising an additional reactive acoustic feature formed in the shell that comprises an additional attenuation profile configured to attenuate the tonal acoustic waves.

17. A silencer module for an air handling unit, comprising:
a first baffle, comprising:
a first shell comprising a first plurality of panels defining a first interior volume of the first baffle and defining a first outer perimeter of the first baffle, wherein the first plurality of panels comprises a first panel having first perforations formed therein; and
a first reactive acoustic feature formed within the first outer perimeter of the first baffle, wherein the first reactive acoustic feature comprises a first throat in fluid communication with an air channel external to the first shell, and the first reactive acoustic feature is separated from the first interior volume by a first plurality of walls of the first baffle; and

a second baffle, comprising:
a second shell comprising a second plurality of panels defining a second interior volume of the second baffle and defining a second outer perimeter of the second baffle, wherein the second plurality of panels comprises a second panel having second perforations formed therein, wherein the first panel is spaced apart from the second panel to form the air channel between the first panel and the second panel; and
a second reactive acoustic feature formed within the second outer perimeter of the second baffle, wherein the second reactive acoustic feature comprises a second throat in fluid communication with the air channel external to the second shell, and the second reactive acoustic feature is separated from the second interior volume by a second plurality of walls of the second baffle,

wherein the first reactive acoustic feature and the second reactive acoustic feature each comprise an attenuation profile configured to reduce propagation of tonal acoustic waves through the air channel.

18. The silencer module of claim 17 , wherein the first baffle comprises sound absorbing material disposed within the first interior volume and in fluid communication with the air channel via the first perforations, wherein the sound

Assignees

• Air Distribution Tech Ip Llc
• Tyco Fire & Security Gmbh

Inventors

• Balaguru Rajavel
• Bauch Paul F
• Howard Roger Lee

Classifications

• G10K11/172

  using resonance effects · CPC title

• F24F2013/245

  using resonance · CPC title

• F24F2013/242

  Sound-absorbing material · CPC title

• G10K11/161

  in systems with fluid flow (G10K11/162 takes precedence; gas flow silencers or exhaust apparatus for machines or engines in general or for internal combustion engine F01N, noise absorbers in pipes or pipe systems F16L55/02; noise absorption in air conditioning and ventilation F24F13/24; silencing exhaust or propulsion jets in aircraft B64D33/06) · CPC title

• G10K11/162 Primary

  Selection of materials · CPC title